1. Field of the Invention
The present invention relates to a geographical information processing system, and more particularly, to a navigation system for downloading information about a position adjacent to a current user position using a wireless network to display the downloaded information on a screen and method thereof. The present application is based on KPA 00-28655, which is incorporated herein by reference.
2. Description of the Related Art
In general, navigation systems are provided with map information and display a navigation function to users. FIG. 1 shows a navigation screen in a conventional automobile navigation system. Referring to FIG. 1, the navigation screen includes map data, administrative district data, graphical feature and object data for a route from Seoul to Daegu. In this case, the map data may have several levels depending on a reduced scale and detailed information. The administrative district information may have data that varies depending on levels of map data. The graphical feature and object data includes information about gas stations, hospitals, and schools, and control data may be added to each graphical feature and object.
To display the navigation screen as shown in FIG. 1, the conventional navigation system calculates navigation data using one of the following methods. The first method is to store all navigation data of the whole country in a memory since the navigation system cannot predict the direction in which the user travels. The second one is for the navigation system to download all necessary data for a route between a desired destination and a selected starting point, which are designated in advance from a navigation data server of a personal computer. This is used for the case in which the navigation system lacks a memory space for storing all data for the whole country.
However, the first method cannot be applied to a small-sized navigation system in which a memory size is small and performance is low since all navigation data needs to be stored in a memory. Furthermore, to apply the second method, a navigation system must have all downloaded data for a corresponding route, and in particular if the starting point and the desired destination are changed, the second method cannot be used.
Therefore, conventional navigation systems to which the above methods are applied suffer from a drawback in that the efficiency of the overall system is degraded since as more data is stored, more capacity is allocated for searching for necessary information and processing the searched information.
To solve the above problems, it is an objective of the present invention to provide a navigation system for improving its efficiency by downloading only necessary information about an adjacent position from a server using a tracking system and method thereof.
Accordingly, to achieve the above objective, the present invention provides a method of processing navigation information in a navigation system including a database, the method comprising the steps of: (a) setting a starting point, a destination, and specific information to be displayed on a screen; (b) calculating a current user position based on position information received via a wireless network and identification (ID) information; (c) if information about a position adjacent to the current user position calculated in the step (b) is stored in the database, displaying a user movement based on the stored information, and if not, requesting a server to send specific information about the adjacent position which is set in the step (a); and (d) if the specific information about the position adjacent to the current user position, which is requested in the step (c), is searched for by the server, downloading only the specific information to display the downloaded result on a screen while displaying a user movement on the corresponding screen.
The present invention also provides a navigation system including: a navigation unit which transmits current user position information to a server after calculating the current user position using position information received via a wireless network to request only specific information about a position adjacent to the current user position, and which displays a user movement based on the specific information about the adjacent position after downloading the specific information about the adjacent position from the server; and a server which searches for only the specific information about the adjacent position with respect to the current position according to the current user position and the request for the specific information about the adjacent position received from the navigation unit and transmits the searched result to the navigation unit.